Best Practices and Resources For Custom Coding, Perfomance and Capacity Planning
Perfomance of a MOSS site is the most important factor for a MOSS site. Its not so easy to write custom application using Sharepoint Object MOdel.
Recently Microsoft has Added technical articels as follows
Performance and Capacity Planning Resource Center for SharePoint Server 2007
This page contains resources to help you with performance and capacity planning for your SharePoint Server deployment—map your solution design to a farm size and set of hardware that supports your business goals.
Best Practices Resource Center for SharePoint Server 2007
To avoid common pitfalls and keep your Office SharePoint Server 2007 environment available and performing well, follow these best practices based on real-world experience from Microsoft Consulting Services and the product team.
Best Practices: Common Coding Issues When Using the SharePoint Object Model